1. Field of the Invention
The present invention relates to a storage system including a host computer and a plurality of storage subsystems, and virtualization and load distribution techniques of the storage subsystem.
2. Description of the Related Art
A technique of moving a data for storage subsystem within a single disk control device has been known in a storage subsystem including the disk control device and a physical disk. A load distribution technique across a plurality of disk control devices by adjusting intervals of receiving input/output requests from a host computer has also been known.
For example, Japanese Published Patent Application No. 2006-318012 discloses a technique in which, in a control system in which a plurality of disk controller clusters each for controlling a data transfer between a host computer and a disk drive device are connected, the disk controller clusters are each provided with an in-cluster resource usage monitor for monitoring a resource usage in the disk controller. An in-system resource usage monitor for monitoring a resource in the system is also provided, which collects information monitored by a plurality of in-cluster resource usage monitors and take the information as monitor information on in-system resource usage monitoring. An issue interval of an IO job across a plurality of the disk controller clusters is adjusted based on the monitor information on in-system resource usage monitoring so as to conduct a load distribution of the IO job in the whole system. However, the technique has such problems that the adjustment of the issue interval of an IO job may reduce performance of access to a requested resource and may negatively affect work performance.
To solve the above problems, the present invention has been made in an attempt to provide a storage system, a load distribution management method, and a storage medium which can perform a load distribution between a plurality of disk control devices without affecting performance of host works.